Pre-compliance testing and characterization of equipment shelf EMC behavior by empirical frequency response measurements on the primary power bus

This paper demonstrates a frequency-swept measurement technique for predicting the conducted and radiated emissions performance of equipment shelves for pre-compliance and diagnostic purposes. The technique is based on the use of a vector network analyzer to identify the frequency passbands and resonances of the inherent coupling structure(s) presented by the primary DC power bus of the equipment shelf. The outcomes are compared with independently obtained conducted and radiated emissions spectra for the same equipment. Relevant data are presented and discussed. The technique is well suited for pre-compliance and diagnostic testing. It does not require fully populating nor powering the equipment shelf. The test is easy to perform and the information it provides goes a long way in optimizing or ranking alternate designs for electromagnetic compatibility.